Wamp, WordPress, Woo Commerce error

Installed the latest version of Wamp locally on a Windows XP machine, downloaded and installed the latest version of WordPress, which went fine. Downloaded and attempted to install Woo Commerce locally to test functionality and received the following error when trying to activate the Woo Commerve plugin:

Fatal error: Class ‘WC_API’ not found in C:\Documents and Settings\Mike\My Documents\wamp\www\elegance\wp-content\plugins\woocommerce\woocommerce.php on line 142

I am not well versed in PHP and am assuming it is a possible issue with WAMP/php settings. Any guidance would be greatly appreciated. I apologize if I have omitted any necessary data.

Thank you.